The present invention relates to an arrangement for dispensing, simultaneously, over the entire vertical and/or longitudinal extent of a body of fluid a gelling agent which will gel each increment of the body of fluid simultaneously so that it is immediately contained against any spilling or contamination of the handler.
More particularly, this invention relates to such an arrangement which contains a body of gelling agent for insertion and exposure to a body of fluid containing contaminated agents which must be contained immediately following the collection of the body of fluid. In particular, one preferred use of the invention here is the immediate containment of collected fluids in a suction canister used in the operating room for collecting body fluids, which may or may not be contaminated, during an operating procedure. It will be understood by practitioners in the art, however, that the device of the invention may be used for rapid control and gelation of any contained body of aqueous containing fluid.
One of the features of the invention is that the particular arrangement herein reduces the "diffusion length" of the gelling material moving from its contained arrangement to and over the entire body of fluid. Because of this shortened diffusion length, there is, as discussed above, a simultaneous immediate containment of each portion of the liquid being contained.
Suction canisters have been used for a period of years for collecting and containing body fluids during an operation. In general, suction canisters employ a collection system and a vacuum source, such as a pump, to facilitate the drainage procedure. Each canister usually includes a flexible line or hose connected to the vacuum source so that vacuum can be applied to the interior of the canister. Another line extends from the source of body fluids at the patient to the canister. Thus, when a negative pressure gradient is applied across the canister, body fluids are drawn into the canister.
However, due to the fear of contamination of body fluids, including, for example, blood from an AIDS patient or a patient suffering from hepatitis, it has become increasingly important to contain these collected fluids immediately after collection. In removing a container from its collection position and moving it about for disposal, it is relatively easy to spill such liquids and it is to this problem to which this invention is particularly directed.
Arrangements have been made in the past and are well known for gelling fluids. For example, U.S. Pat. Nos. 4,748,069 and 4,749,600 are both directed toward packets containing gelation material for introduction into a shipping container or carton for gelling liquid that leaks from broken bottles, vessels, or other packages. These packets are placed next to a collection vessel for inadvertent leakage containment.
If gelling agents are added to the canister in the form of dissolvable packets, the packets may sink or float and the gelling material itself is exposed only to the fluid immediately adjacent the surface thereof for the first gelling activity. This is a result of the volume configuration constraints of the canister.
Because of this, portions of the active gelling material may become encapsulated within the gel and result in an incomplete or partially gelled liquid matrix. Diffusion of the gel powder through the fluid is restricted initially by the viscosity of the body fluids themselves and later by the viscosity build associated with the gelling process. When the canister is subsequently discarded, the partial or incomplete gelled fluid may leak and/or burst for exposing those individuals who are handling the disposed canisters such as janitors, cleaning personnel, and the like.
A complication associated with pouring the powder into a filled canister is that there is sometimes not sufficient head space between the lid and liquid surface to accommodate the required volume of powder. As a result, the filled canister must be shaken or swirled to mix the powder and avoid the premature encapsulation and clumping. Hospital personnel should not swirl the filled canister because of the chance of leakage around the lid area. In addition, another obvious problem associated with handling free flowing powder is that it can be inadvertently spilled in the operating area as it is being poured into the canister.
Other arrangements in the past include merely pouring or sprinkling the gelation material on the top of the body of fluid in a canister for the gelation thereof. The same problems arise as described above in that that gelling material is not exposed to, for example, the bottom portion of the contained liquid for immediate absorption thereof.
With this invention, by contrast, an arrangement is provided in the form of an elongated rigid or semi rigid structure for containing a dissolvable packet of gelling material for introduction into, for example, the liquid contained in a suction canister. Because the outer supporting structure is rigid or semi rigid, and contains windows for exposure of the contained envelope of gelling material, the device may be positioned to extend over the entire vertical extent, for example, of the collected fluid. Thus, each increment of the liquid over the vertical extent thereof is immediately, and simultaneously, exposed to the gelling material so that there is no encapsulation or clumping and all increments of the collected fluid are immediately gelled. For this reason, with the invention here, there are no pockets left of partially gelled or ungelled liquids.
Furthermore, the elongated rigid or semi rigid structure may be placed in the canister through an opening in the lid after the canister is filled with body fluids. This eliminates the shortcomings described above.
As a further feature of this invention, it is contemplated that the device or arrangement of the invention may be positioned initially in a suction canister when it is manufactured, or at least prior to any use thereof. Because of this, when liquid is introduced or collected into the suction canister, those portions initially introduced are immediately gelled, and as the container is filled, each increment adjacent the vertical extent of the container and the device positioned therein is immediately gelled upon collection. Because of this, the collected contaminated fluid is immediately contained for subsequent disposal with no problems of liquid spillage and contamination of those handling the canister.
Alternatively, the device of the invention may be inserted by a lab technician after examination of the canister contents for a required analysis of the collected fluid.
Before describing this invention in more detail, it may be well to note that the elongated structure of the invention is arranged to extend over the entire vertical extent, for example, of a suction canister internal cavity, or other aqueous fluid containing container. As such, the arrangement has elongated windows over the vertical extent thereof so as to expose, at each elevation from the bottom surface to the top of the internal cavity of the container, the gelling agent.
Windows are arranged in a variety of configurations, as will be described below, for exposing the packet of gelling material to the liquid collected. It is within the purview of this invention that the elongated arrangement or device of the invention may be placed and fixed internally of the container, as discussed above, for receiving and gelling immediately the collected material. Representative materials which may be used for the containing device of the invention include, for example, rigid and semi rigid thermoplastic materials which may be readily molded in a conventional technique and mass produced for low cost production. The devices may be, for example, oval, triangular, or square in cross section. They may include a press fit cap on one end thereof for receiving the packet of gelling material.
Finally, the gelling material may be contained in an elongated package of material entirely dissolvable in an aqueous containing liquid. The packet may have an adhesive along one side edge for adhering the packet in the desired position to one side edge of the collection container.
The gelling material may be, for example, known gelling material for aqueous liquids, such as sodium polyacrylate as disclosed in the above noted U.S. patents. Commercial products using polyacrylate gelling agents for suction canisters are, for example, RED-Z.TM. (Medzam, Ltd., North Tonowanda, N.Y.), and LiquiSorb.RTM. (American Colloid Company, Arlington Heights, Ill.). Other representative gelation materials include highly absorbent products consisting of starch modified with pendent grafted acrylonitrile, acrylamide and sodium acrylate groups such as those disclosed in U.S. Pat. Nos. 3,661,815 and 4,302,369, such materials being available from Grain Processing Corporation, Muscatine, Iowa, under the tradename Water Lock.RTM..
A preferred gelling agent useful in the device of the invention may be that disclosed and taught in co-pending U.S. Patent application Ser. No. 07/476,869 filed Feb. 7, 1990, which teaches a gelling composition for an aqueous liquid including an ungelated starch which has been reacted with a silane coupling agent. The material may include, for example, a disinfectant for handling con taminated body fluids, as discussed above.
Other objects and advantages of this invention will be apparent from the following description, the accompanying drawings and the appended claims.